Which statement accurately describes how WDXRF and EDXRF differ in detector technology and typical use?

• A. WDXRF uses a crystal to separate wavelengths for high-resolution spectra; EDXRF uses a crystal for energy-dispersive spectra.
• B. WDXRF uses a crystal to separate wavelengths for high-resolution spectra; EDXRF uses a silicon-based detector for energy-dispersive spectra.
• C. WDXRF relies on a simple light detector, while EDXRF uses multiple detectors.
• D. EDXRF cannot analyze solids.

Answer: (B)

The main idea is how the detector separates and measures X-ray energies. WDXRF uses a diffraction crystal to separate X-rays by wavelength, giving high spectral resolution so individual emission lines are clearly distinguished. This makes WDXRF especially good for precise quantitation in complex samples where lines can overlap, such as minerals or alloys.

EDXRF uses a silicon-based detector (like a silicon drift detector or Si-PIN diode) to measure the energy of incoming photons directly, producing an energy-dispersive spectrum. It’s faster and more convenient for routine or in-field analysis of solids or powders, but the spectral resolution is lower than with crystal-based WDXRF, which is why it’s often used for quick screening rather than highly resolved, quantitative work.